Abstract

An ultrawide band quantum dot(QD)light emitting device(LED) with bandwidth of covering spectral range has been demonstrated by postfabrication laser-irradiation technique. The integrated light output of the QDLED was found to increase by four times after laser annealing, attributed to the improved homogeneity of the QDs and enhanced lateral electrical and optical confinements at the active region after intermixing. Large wavelength blueshift of has been obtained at the laser annealed region and an overall increase in bandwidth of 22% has been obtained in the QDLED after postfabrication laser annealing.

Received 12 October 2006Accepted 08 January 2007Published online 05 February 2007

Acknowledgments:

This work is supported by the Institute of Materials Research and Engineering. The authors would like to thank Dominic T. W. Dang, W. P. Khet, and Y. F. Chau for their help in device fabrication and characterization.